Electrical switches are provided with contact materials that facilitate the travel of current through the switch. The contact materials are can be made of a metal alloy. Alloys used in switches designed to carry large currents (>15 amps) are can be fabricated by powder metallurgy or internal oxidation processes. Consequently, these materials include a heterogeneous mixture of alloy constituents. As the switch is cycled between numerous make/break cycles the surface of the contact materials are subjected to momentary periods of extreme heat, causing the surface of the contact to melt, briefly, and then re-solidify. For many alloys used as switch contact materials, the brief period of melting causes the constituents comprising the alloy to undergo a small amount of phase separation because the molten silver does not favorably wet, the surface of the metal oxide. Gradually, the switch contact surface takes on a lamellar composition characterized by silver-rich layers and metal oxide-rich layers. Ultimately, the metal oxide-rich layers lead to high resistivity and switch failure.